digitalmars.D - casting objects is not working across dll boundaries

Consider the following code:
module sharedInterface;
class A {}
module mainExecutable;
import sharedInterface;
import core.stdc.stdio;
extern(C)
{
alias Object function() MakeObjectFunc;
}
__gshared MakeObjectFunc MakeObject;
void main(string[] args)
{
//Load the dll with LoadLibrary and
//get the address of MakeObject with GetProcAdress
auto obj = cast(A)MakeObject();
printf("obj = %x\n", cast(void*)obj);
}
module dll;
extern(C) export Object MakeObject()
{
return new A();
}
The modules sharedInterface and mainExecutable are compiled into a
executable. The modules dll and sharedInterface are compiled into a dll.
The exexutable will print
obj = 0x0
Because the _d_isbaseof2 in cast_.d does not work across dll boundaries.
It always uses the "is" operator for comparing two TypeInfo_Class
objects, which breaks the dll support. Now this can be fixed, but it
would require a full compare each time which would make casting
significantly slower.
Should this be fixed or do we want to wait for a shared dll version of
druntime?
I also found that inside Thread.remove
if( sm_tbeg == t )
sm_tbeg = t.next;
Will crash across dll boundaries inside object_.d opEquals(Object,
Object) because the vtable of one of the objects is invalid. Using the
is operator instead of the compare fixed it for me.
Kind Regards
Benjamin Thaut